The word Invertebrate describes any animal which does not have a spine. Although lacking an internal skeleton, many invertebrates make up for this by developing a shell (as with snails), or a hard exoskeleton that protects their entire body (as with lobsters and insects.) Having a shell doesn't qualify an animal as an invertebrate, however; many invertebrates are soft-bodied, relying on other ways to protect themselves from their environment. Click here for more info...

The Portgueses Man of War, a species of jellyfish, can have venomous, stinging tentacles up to 164 feet long!
 
A-Z List of all Invertebrates
Ant Crab Hermit Crab Nautilus Star Fish
Army Ant Crawfish Honeypot Ant Octopus Tapeworm
Bedbug Daddy Long Legs Hermit Crab Oyster Tarantula
Bee Dragonfly Horseshoe Crab Praying Mantis Termite
Beetle Driver Ant Jellyfish Roundworm Tick
Black Widow Spider Dust Mite Krill Scallop Trap Jaw Ant
Bulldog Ant Earthworm Leafcutter Ant Scorpion Walking Stick
Butterfly Fire Ant Leech Sea Anemone Wasp
Camel Spider Flatworm Lobster Sea Urchin Weaver Ant
Caterpillar Flea Louse Shrimp  
Centipede Fly Millipede Snail  
Clam Giant Clam Mosquito Spider  
Cockroach Giant Squid Moth Sponge  
Coral Green Ant Mussel Squid  

 

 
Click on the individual animals below to get more facts.